• Caesium Fluoride-Mediated Hydrocarboxylation of Alkenes and Allenes: Scope and Mechanistic Insights 

      Gevorgyan, Ashot; Obst, Marc; Guttormsen, Yngve; Maseras, Feliu; Hopmann, Kathrin Helen; Bayer, Annette (Journal article; Tidsskriftartikkel; Peer reviewed, 2019-09-11)
      A caesium fluoride-mediated hydrocarboxylation of olefins is disclosed that does not rely on precious transition metal catalysts and ligands. The reaction occurs at atmospheric pressures of CO<sub>2</sub> in the presence of 9-BBN as a stoichiometric reductant. Stilbenes, β-substituted styrenes and allenes could be carboxylated in good yields. The developed methodology can be used for preparation of ...
    • Caffeine supplementation does not affect match activities and fatigue resistance during match play in young football players 

      Pettersen, Svein Arne; Krustrup, Peter; Bendiksen, Mads; Randers, Morten B.; Brito, Joao; Bangsbo, Jens; Yun, Jin; Mohr, Magni (Journal article; Tidsskriftartikkel; Peer reviewed, 2014-10-30)
      The study examined the effect of caffeine supplementation on match activities and development of fatigue during a football match. In a randomised, double-blind cross-over design, two experimental football games separated by 7 days were organised between the junior teams of two professional football clubs (17.6 ± 1.1 years (±s), 71.7 ± 6.9 kg, 13.9% ± 5.0% body fat). The players ingested either a ...
    • Calculations of the EPR g-tensor using unrestricted two- and four-component relativistic approaches within the HF and DFT frameworks 

      Cherry, Peter J.; Komorovsky, Stanislav; Malkin, Vladimir G.; Malkina, Olga L. (Journal article; Tidsskriftartikkel; Peer reviewed, 2016-06-08)
      Approaches and programs for calculations of the EPR g-tensor in the framework of the two- and four-component methods are still very rare. There are three main reasons for this: the wider community's unawareness of the importance of second- and higher order spin–orbit effects on the g-tensor, the methodological problems associated with performing such calculations and the lack of understanding of ...
    • Can the absolute configuration of cyclic peptides be determined with vibrational circular dichroism? 

      Eikås, Karolina Di Remigio; Monika, Krupová; Kristoffersen, Tone; Beerepoot, Maarten; Ruud, Kenneth (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-04-16)
      Cyclic peptides show a wide range of biological activities, among others as antibacterial agents. These peptides are often large and flexible with multiple chiral centers. The determination of the stereochemistry of molecules with multiple chiral centers is a challenging and important task in drug development. Chiroptical spectroscopies such as vibrational circular dichroism (VCD) can ...
    • Carbon-carbon bonds with CO2: Insights from computational studies 

      Obst, Marc; Pavlovic, Ljiljana; Hopmann, Kathrin Helen (Journal article; Tidsskriftartikkel; Peer reviewed, 2018-02-17)
      In this mini-review, we provide an overview of recent computational studies on homogeneous transition metal-catalyzed carbon-carbon bond formation with CO2. We cover substitution and addition reactions involving different metals (mainly Ni, Rh, Cu) and substrates (alkanes, alkenes, alkynes, arenes) with focus on the mechanistic details. The CO2 insertion step is generally found to be rate-limiting. ...
    • Carbonylative Suzuki-Miyaura couplings of sterically hindered aryl halides: Synthesis of 2-aroylbenzoate derivatives 

      Ismael, Aya; Skrydstrup, Troels; Bayer, Annette (Journal article; Tidsskriftartikkel; Peer reviewed, 2020-02-10)
      We have developed a carbonylative approach to the synthesis of diversely substituted 2-aroylbenzoate esters featuring a new protocol for the carbonylative coupling of aryl bromides with boronic acids and a new strategy to favour carbonylative over non-carbonylative reactions. Two different synthetic pathways – (i) the alkoxycarbonylation of 2-bromo benzophenones and (ii) the carbonylative Suzuki–Miyaura ...
    • Catalytic Intermolecular Functionalization of Benzimidazoles 

      Hansen, Jørn H; Fjellaksel, Richard (Peer reviewed; Chapter; Bokkapittel, 2019-06-25)
      This chapter describes contemporary strategies for selective catalytic intermolecular functionalization of the benzimidazole scaffold. Functionalization at nitrogen and position C-2 is well developed employing copper, palladium, rhodium, nickel, and cobalt catalysis. Direct CH activation is the predominant approach to C-2 functionalization. Nickel-based catalysts can activate C—O bonds in conjunction ...
    • Cavity-Free Continuum Solvation: Implementation and Parametrization in a Multiwavelet Framework 

      Gerez Sazo, Gabriel Adolfo; Remigio Eikås, Roberto Di; Jensen, Stig Rune; Bjørgve, Magnar; Frediani, Luca (Journal article; Tidsskriftartikkel; Peer reviewed, 2023-03-18)
      We present a multiwavelet-based implementation of a quantum/classical polarizable continuum model. The solvent model uses a diffuse solute–solvent boundary and a position-dependent permittivity, lifting the sharp-boundary assumption underlying many existing continuum solvation models. We are able to include both surface and volume polarization effects in the quantum/classical coupling, with guaranteed ...
    • Centre for Digital Life Norway - Annual report 2017 

      Ukjent forfatter (Research report; Forskningsrapport, 2018)
      Centre for Digital Life Norway (DLN) is a virtual centre, institutionally anchored at NTNU, UiO and UiB. It is funded by the Research Council of Norway under the Digital Life (DL) initiative and receives in kind support from the host universities. The centre is built around the 12 research projects are currently funded through the research council’s Digital Life initiative. DLNs mission is ...
    • Channel interference in multiphoton absorption 

      Alam, MD Mehboob; Beerepoot, Maarten; Ruud, Kenneth (Journal article; Tidsskriftartikkel; Peer reviewed, 2017-06-30)
      We extend the theory of channel interference to higher-order multiphoton absorption processes. We derive an explicit expression for channel interference in a three-photon absorption process and propose a general scheme for deriving such expressions for multiphoton absorption processes of any order. Based on this general scheme, we derive and analyze the simplest few-state models for multiphoton ...
    • Characterization and engineering of a DNA polymerase reveals a single amino-acid substitution in the fingers subdomain to increase strand-displacement activity of A-family prokaryotic DNA polymerases 

      Piotrowski, Yvonne; Gurung, Man Kumari; Larsen, Atle Noralf (Journal article; Tidsskriftartikkel; Peer reviewed, 2019-08-09)
      <i>Background</i> - The discovery of thermostable DNA polymerases such as Taq DNA polymerase revolutionized amplification of DNA by polymerase chain reaction methods that rely on thermal cycling for strand separation. These methods are widely used in the laboratory for medical research, clinical diagnostics, criminal forensics and general molecular biology research. Today there is a growing demand ...
    • Characterization of a cold-active and salt tolerant esterase identified by functional screening of Arctic metagenomic libraries 

      De Santi, Concetta; Altermark, Bjørn; Pierechod, Marcin Miroslaw; Ambrosino, Luca; de Pascale, Donatella; Willassen, Nils Peder (Journal article; Tidsskriftartikkel; Peer reviewed, 2016-01-19)
      Background: The use of metagenomics in enzyme discovery constitutes a powerful approach to access to genomes of unculturable community of microorganisms and isolate novel valuable biocatalysts for use in a wide range of biotechnological and pharmaceutical fields. Results: Here we present a novel esterase gene (lip3) identified by functional screening of three fosmid metagenomic libraries, ...
    • Characterization of an intertidal zone metagenome oligoribonuclease and the role of the intermolecular disulfide bond for homodimer formation and nuclease activity 

      Piotrowski, Yvonne; Berg, Kristel; Klebl, David Paul; Leiros, Ingar; Larsen, Atle Noralf (Journal article; Tidsskriftartikkel; Peer reviewed, 2019-08-17)
      The gene encoding MG Orn has been identified from a metagenomic library created from the intertidal zone in Svalbard and encodes a protein of 184 amino acid residues. The <i>mg orn</i> gene has been cloned, recombinantly expressed in <i>Escherichia coli</i>, and purified to homogeneity. Biochemical characterization of the enzyme showed that it efficiently degrades short RNA oligonucleotide substrates ...
    • Chemical Analysis and Anthelmintic Activity Against Teladorsagia Circumcincta of Nordic Bark Extracts In vitro 

      Athanasiadou, Spiridoula; Almvik, Marit; Hellström, Jarkko; Madland, Eva; Simic, Nebojsa; Steinshamn, Håvard (Journal article; Tidsskriftartikkel; Peer reviewed, 2021-06-04)
      Helminth parasitic infections are common in small ruminants in Norway; infection is usually treated with anthelmintic drugs, but anthelmintic resistance is an increasing problem. It is necessary to identify strategies to reduce the use of anthelmintic drugs and mitigate the impact of anthelmintic resistance. Condensed tannin (CT)-rich forages have been shown to reduce the helminth burden in small ...
    • Chemo-inspired Genetic Algorithm for Optimizing the Piecewise Aggregate Approximation 

      Muhammad Fuad, Muhammad Marwan (Journal article; Tidsskriftartikkel; Peer reviewed, 2015)
      In a previous work we presented DEWPAA: an improved version of the piecewise aggregate approximation representation method of time series. DEWPAA uses differential evolution to set weights to different segments of the time series according to their information content. In this paper we use a hybrid of bacterial foraging and genetic algorithm (CGA) to set the weights of the different segments in our ...
    • Chemometric analysis for pollution source assessment of harbour sediments in Arctic locations 

      Pedersen, Kristine Bondo; Lejon, Tore; Jensen, Pernille E.; Ottosen, Lisbeth M. (Journal article; Tidsskriftartikkel; Peer reviewed, 2015-04-16)
      Pollution levels, pollutant distribution and potential source assessments based on multivariate analysis (chemometrics) were made for harbour sediments from two Arctic locations; Hammerfest in Norway and Sisimiut in Greenland. High levels of heavy metals were detected in addition to organic pollutants. Preliminary assessments based on Principal Component Analysis (PCA) revealed different sources and ...
    • Chiral recognition by fullerenes: CHFClBr enantiomers in the C82 cage 

      Dodziuk, Helena; Ruud, Kenneth; Korona, Tatiana; Demissie, Taye Beyene (Journal article; Tidsskriftartikkel; Peer reviewed, 2016-08-18)
      Density-functional theory and symmetry-adapted perturbation theory calculations on complexes of the enantiomers of CHFClBr with the most stable isomer of C<sub>82</sub>-3 fullerene show that despite the guests being too large for the host cage, they are nevertheless stabilized by electrostatic interactions. The complexation leads to considerable strain on the cage and the guests accompanied by ...
    • Choosing Bad versus Worse: Predictions of Two-Photon-Absorption Strengths Based on Popular Density Functional Approximations 

      Chołuj, Marta; Alam, MD Mehboob; Beerepoot, Maarten; Sitkiewicz, Sebastian P.; Matito, Eduard; Ruud, Kenneth; Zaleśny, Robert (Journal article; Tidsskriftartikkel; Peer reviewed, 2022-01-26)
      We present a benchmark study of density functional approximation (DFA) performances in predicting the two-photon-absorption strengths in π-conjugated molecules containing electron-donating/-accepting moieties. A set of 48 organic molecules is chosen for this purpose, for which the two-photon-absorption (2PA) parameters are evaluated using different DFAs, including BLYP, PBE, B3LYP, PBE0, CAM-B3LYP, ...
    • Closely-related Photobacterium strains comprise the majority of bacteria in the gut of migrating Atlantic cod (Gadus morhua) 

      Le Doujet, Typhaine; De Santi, Concetta; Klemetsen, Terje; Hjerde, Erik; Willassen, Nils Peder; Haugen, Peik (Journal article; Tidsskriftartikkel; Peer reviewed, 2019-04-17)
      <p><i>Background - </i>The population of Atlantic cod (<i>Gadus morhua</i>), also known as Northeast Arctic cod, migrating Atlantic cod, or simply “skrei,” lives mainly in the Barents Sea and Svalbard waters and migrates in annual cycles to the Norwegian coast in order to spawn eggs during late winter. It is the world’s largest population of Atlantic cod, and the population is distinct from the ...
    • Co-cultivation and transcriptome sequencing of two co-existing fish pathogens Moritella viscosa and Aliivibrio wodanis 

      Hjerde, Erik; Karlsen, Christian; Sørum, Henning; Parkhill, Julian; Willassen, Nils Peder; Thomson, Nicholas R. (Journal article; Tidsskriftartikkel; Peer reviewed, 2015-06-10)
      Background: Aliivibrio wodanis and Moritella viscosa have often been isolated concurrently from fish with winterulcer disease. Little is known about the interaction between the two bacterial species and how the presence of one bacterial species affects the behaviour of the other. Results: The impact on bacterial growth in co-culture was investigated in vitro, and the presence of A. wodanis has an ...